Optical techniques for data processing are known as those providing ultra fast data processing capabilities that are independent of electrical cross talk and induced noises. Existing all-optical devices for data processing are based on the use of non-linear effects achieved by light propagation through a non-linear medium. The non-linear effect is thus obtained via light interaction with electrons of the material due to non-linear oscillations of electrons.
Such devices are described for example in U.S. Pat. Nos. 5,150,248; 5,373,381 and 5,463,485 which disclose optical computing systems, communication systems, and logic elements using cross-phase modulation based optical processors to alter and control, either alone or simultaneously, the spectral, temporal and/or spatial properties of ultrashort light pulses for processing information with high speed repetition rates. A weak beam of ultrashort light pulses is modulated by an intense beam of ultrashort light pulses by copropagating both beams through a non-linear medium such that cross-phase modulation effects are realized.
However, in order to achieve non-linear effects of interaction between light beams in a non-linear medium, intense operating illumination and a large interaction region are required. Moreover, the response time of the non-linear effects is finite. This is because the effect of light interaction with electrons of the material cannot be achieved immediately.